> Hmm.  It seems better to me to accept this bug (and document it, and
> point out that it isn't Python's fault) than depriving 64-bit users
> of IDLE, or (even worse) of tkinter.

I disagree. There aren't really "64-bit users" on OSX, thanks to fat
binaries. So if starting IDLE would start a 32-bit interpreter, users
likely won't even notice. If they do notice, they can still run in
64-bit mode from the command line.

In my experience with fat python builds on OSX, it's typically better
to prefer 32-bit mode, anyway, as extension modules often don't come
in a fat version, but often in 32-bit mode only.